The genomic sequence of the fission yeast S. pombe will soon be published. This yeast provides a powerful genetic and molecular system, which is currently the major focus of study for about 40 laboratories in the U.S., and an even larger number in Europe and Japan. Many of the laboratories in the U.S., including those of Drs. Janet Leatherwood and A. Bruce Futcher, work on the cell cycle, for which S. pombe is an excellent model organism. Spotted cDNA microarrays are a cheap, rapid, efficient method for collecting data and investigating many subjects from cell physiology and transcription circuits to chromosome structure, mRNA splicing, translational regulation, DNA replication control, and meiotic recombination. Here, it is proposed to create a facility for the production and use of S. pombe cDNA microarrays. These microarrays would be available to the community of S. pombe workers in the U.S., and, if resources permit, to workers in other countries. Microarrays would be made at a facility at the SUNY, Stony Brook. Outside users of the facility would do experiments designed for microarray analysis, isolate RNA (or DNA), validate the samples, and convert the RNA to labeled cDNA or label the isolated DNA. This labeled DNA would be sent to the facility, where it would be hybridized to the microarrays, scanned, and subjected to standard forms of analysis. Results would be posted to a Web site for further analysis by the user. Resources for more extensive data analysis would be available on the facility?s Web site.